I think the thought process is that he would not see the field unless Brown or Doubs came off the field, which could cause him to become a malcontent in a contract season. He’s not really a player for the slot, and if they are taking one of their outside guys off the field, they may want to prioritize playing one of the guys they want to develop for the future like Williams.
I have no issues with keeping him if they think things will be fine, but also no issues with moving him - of course assuming Brown is acquired.